Method and system for forming a precursor compound for non-bridged unsymmetric polyolefin polymerization catalyst

ABSTRACT

The present techniques relates generally to polyolefin catalysts and, more specifically, to preparing a precursor compound for an unsymmetric metallocene catalyst, for using the precursor compound to prepare catalysts, and for employing the precursor compounds to prepare catalysts for polyolefin polymerizations.

BACKGROUND

The present techniques relates generally to polyolefin catalysts and,more specifically, to preparing a precursor compound for an unsymmetricmetallocene catalyst, for using the precursor compound to preparecatalysts, and for employing the precursor compounds to preparecatalysts for polyolefin polymerizations.

This section is intended to introduce the reader to aspects of art thatmay be related to aspects of the present techniques, which are describedand/or claimed below. This discussion is believed to be helpful inproviding the reader with background information to facilitate a betterunderstanding of the various aspects of the present techniques.Accordingly, it should be understood that these statements are to beread in this light, and not as admissions of prior art.

As chemical and petrochemical technologies have advanced, the productsof these technologies have become increasingly prevalent in society. Inparticular, as techniques for bonding simple molecular building blocksinto longer chains (or polymers) have advanced, the polymer products,typically in the form of various plastics, have been increasinglyincorporated into various everyday items. For example, polyolefinpolymers, such as polyethylene, polypropylene, and their copolymers, areused for retail and pharmaceutical packaging, food and beveragepackaging (such as juice and milk bottles), household containers (suchas pails and boxes), household items (such as appliances, furniture,carpeting, and toys), automobile components, pipes, conduits, andvarious industrial products.

Specific types of polyolefins, such as high-density polyethylene (HDPE),have particular applications in the manufacture of blow-molded andinjection-molded goods, such as food and beverage containers, film, andplastic pipe. Other types of polyolefins, such as low-densitypolyethylene (LDPE), linear low-density polyethylene (LLDPE), isotacticpolypropylene (iPP), and syndiotactic polypropylene (sPP) are alsosuited for similar applications. The mechanical requirements of theapplication, such as tensile strength and density, and/or the chemicalrequirements, such thermal stability, molecular weight, and chemicalreactivity, typically determine what polyolefin or type of polyolefin issuitable.

To achieve these properties, various combinations of reaction systemsmay be used. For example, to form lower density products, such as LDPEand LLDPE, among others, two monomers may be polymerized together, i.e.,co-polymerized. This forms a polymer that is described as having“short-chain branching.” Other polymers may have links between chainsformed, called “long-chain branching,” while yet other polymers may haveminimal branching of either type. Favorable properties may be obtainedfor polymers that are formed as in-situ blends of these types ofbranched polymer chains, such as in a single reactor using two differentcatalysts. The properties obtained for these blends may be determined bythe molecular weights of each of the polymers and by which polymer isbranched, e.g., short or long chains, among others. To obtain polymershaving high strength and ease of processability, the branching shouldgenerally be confined to the higher molecular weight polymer.Accordingly, continuing efforts in catalyst research are directedtowards developing mixed catalyst systems that may be used to formin-situ polymer blends, as well as more efficient ways of making thesemixed catalyst systems.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an ¹H-NMR (CDCl₃) spectrum of Example Reaction 1 in accordancewith embodiments of the present techniques;

FIG. 2 is an ¹H-NMR (CDCl₃) spectrum of Example Reaction 2 in accordancewith embodiments of the present techniques;

FIG. 3 is an ¹H-NMR (CDCl₃) spectrum of(1-allylindenyl)(n-butylcyclopentadienyl)zirconium in accordance withembodiments of the present techniques;

FIG. 4 is an ¹H-NMR (CDCl₃) spectrum ofbis(n-butylcyclopentadienyl)(zirconium dichloride) for comparativepurposes; and

FIG. 5 is a comparison of proton NMR(CDCl₃) results for Example reaction6 in accordance with embodiments of the present techniques.

DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS

One or more specific embodiments of the present techniques will bedescribed below. In an effort to provide a concise description of theseembodiments, not all features of an actual implementation are describedin the specification. It should be appreciated that in the developmentof any such actual implementation, as in any engineering or designproject, numerous implementation-specific decisions must be made toachieve the developers' specific goals, such as compliance withsystem-related and business-related constraints, which may vary from oneimplementation to another. Moreover, it should be appreciated that sucha development effort might be complex and time consuming, but wouldnevertheless be a routine undertaking of design, fabrication, andmanufacture for those of ordinary skill having the benefit of thisdisclosure.

Molecular weight is an important factor that affects the finalproperties of a polyolefin. Control of molecular weight may be used tocreate polyolefin resins that are strong, chemically resistant, and yeteasily processed in extrusion machines. One way that molecular weightmay be controlled to obtain desirable properties for a polyolefin resinis through the synthesis of bimodal polyolefin resins, i.e., in-situresin blends that combine resins from two distinct molecular weightregions. For example, a high molecular weight resin may provide thebimodal polyolefin with strength and chemical resistance, while a lowmolecular weight resin may provide the bimodal polyolefin with goodprocessability. As resins that have substantial differences in molecularweight are generally not easy to blend, such resins may be created byforming the two molecular weight resins during a single reaction orreaction sequence. This may be performed in a single reactor or insequential reactors.

Another important factor controlling the properties of a final resin isbranching. Branching may take the form of branch points where newpolymer chains grow, termed “long chain branching,” or may be pointswhere carbon chains having double bonds as end groups (comonomers) areincorporated into the polymer backbone, which is termed “short chainbranching.” Short chain branching may be controlled by the concentrationof comonomers added to the polymerization reaction. The comonomers arerandomly incorporated into the polymer backbone, and provide sites wherethe chains may leave a crystallite and join in adjacent crystallites.Generally, in a bimodal polymer, more favorable properties are achievedif the high molecular weight portion has a significant proportion of theshort-chain branching, while the low molecular weight portion has muchless short chain branching. To achieve this, catalyst systems have beendeveloped that both form short molecular weight chains, and also do notsignificantly incorporate comonomer.

The present techniques are directed to catalyst precursors, methods formaking the catalyst precursors, and methods for using the catalystprecursors to manufacture products made from polyolefins. Morespecifically, the present techniques disclose alkenyl substitutedindenyl complexes that may be used as catalyst precursors. The catalystprecursors may be used to form metallocene catalysts capable of formingthe low molecular weight polyolefin portion in a bimodal polyolefin.Further these catalysts may be used with bridged metallocene catalyststhat generally form high molecular weight polyolefins to prepare mixedcatalyst systems that are capable of forming bimodal polymers.

An example of an unbridged metallocene catalyst that may be used toprepare the low molecular weight portion of a bimodal catalyst is shownin the structure illustrated in EQN. 1, below.

In EQN. 1, R and R′ are generally straight chains of 4 to 10 carbons andmay be aliphatic or may have an olefinic (double bond) end group. X is ahalogen ion, such as F, Cl, Br or I (generally Cl), and M is a group IVmetal, such as Ti, Zr, or Hf (generally Zr).

The catalyst structure illustrated in EQN. 1 may generally be preparedby reaction schemes similar to those illustrated in EQN. 2, below.

Method A involves the synthesis and purification of RCpZrCl₃ prior tothe synthesis of the catalyst. However, when R is a straight chainaliphatic or olefinic chain, the resulting compound may be an oil or tarthat may be difficult to purify. Further, Method B generally involvesthe use of tin compounds as intermediates in the synthesis of thecorresponding zirconium trichloride species, which may be difficult toremove after the synthesis. Accordingly, new techniques for synthesizingthese compounds may be desirable.

Techniques for forming these catalysts from new catalyst precursors aredisclosed herein. The synthesis techniques are based on reactions ofallyl-indenyl compounds with metal complexes containing amido ormixed-amido/chloro ligands. The catalyst precursors have the generalformula shown in EQN. 3, below.

In EQN. 3, M may be Ti, Zr, or Hf. Each x may independently be ahydrogen, alkyl, branched alkyl, cycloalkyl, aryl, or alkenyl grouphaving from 2 to 20 carbons. At least one x is the alkenyl group havingfrom 2 to 20 carbons where the alkenyl group is a terminal alkenylgroup, internal alkenyl group (e.g. having cis or transstereochemistry), or a branched alkenyl group (e.g., having Z or Estereochemistry). In certain embodiments, the alkenyl group may haveadditional functionality, such as aromatic, halogen, or silyl moieties.Each Y may independently be a halide or NR₂, where each R mayindependently be a hydrocarbyl group having from 1 to 5 carbons. Each cmay independently be a hydrogen, alkyl, branched alkyl, cycloalkyl,aryl, or alkenyl group having from 2 to 20 carbons. Moreover, in certainembodiments two c groups may be conjoined to form a ring. In anembodiment, for example, the new precursor compound may have the generalformula shown in EQN. 4.

In EQN. 4, n may be 1, 2, 3, 4, 5, 6, 7, or 8. In another embodiment,the precursor compound may have the general formula shown in EQN. 5.

In EQN. 5, n may be 1, 2, 3, 4, 5, 6, 7, or 8, and R may be defined asabove. The ligands on the precursor compound do not have to beidentical, as they may be any combination of halo and amido groups, asillustrated by the embodiment shown in EQN. 6.

In EQN. 6, n and R are defined as above.

A general reaction scheme to form the precursor compounds and then usethe precursor compounds to form the catalyst is shown in EQN. 7.

In EQN. 7, Cp¹ is generally a substituted indenyl and Cp² may be asubstituted cyclopentadienyl, a substituted indenyl, or a substitutedfluorenyl. M may be Ti, Zr, or Hf, and the chlorinating reagent may beHCl, Me₂NH/HCl, or Me₃SiCl, among others. One embodiment of thisreaction scheme is shown in EQN. 8.

Another general technique that may be used to form the catalystprecursor uses organolithium compounds. An example of this technique informing the catalyst precursor, and from that the catalyst, is shown inthe reaction sequence in EQN. 9.

In EQN. 9, M may be Ti, Zr, or Hf. R may be any alkyl having 1 to 10carbons, and R² may be a carbon chain having 4 to 10 carbons and adouble bond between the last two carbons. In a further technique, thereaction sequence can be carried out in a one-pot reaction as shown inEqn 10.

A final technique that may be used to make the catalyst precursor isshown in EQN. 11.

Components that may be used to Form Polymerization Reaction Mixtures

The catalyst systems of the present techniques may include the unbridgedmetallocene catalysts disclosed herein, and may also include atightly-bridged ansa-metallocene compound that has an alkyl or alkenylgroup of three to 20 carbons bonded to a η⁵-cyclopentadienyl-type ligand(such as, for example, a cyclopentadienyl, an indenyl, or a fluorenyl).A general description of the ansa-metallocene complex is presented inthe following subsection. The subsections that follow after that discussother components that may generally be present in an active olefinpolymerization, including the solid oxide support/activator, thealuminum cocatalyst, and a monomer/comonomer.

A. Tightly Bridged Metallocene Catalysts

The tightly bridged metallocene compound may be useful for generatingthe higher molecular weight segment with reasonable comonomerincorporate, as discussed herein. Generally, the term “bridged” or“ansa-metallocene” refers to a metallocene compound in which the twoη⁵-cycloalkadienyl-type ligands in the molecule are linked by a bridgingmoiety. Useful ansa-metallocenes may be “tightly-bridged,” meaning thatthe two η⁵-cycloalkadienyl-type ligands are connected by a bridginggroup wherein the shortest link of the bridging moiety between theη⁵-cycloalkadienyl-type ligands is a single atom. The metallocenesdescribed herein are therefore bridged bis(η⁵-cycloalkadienyl)-typecompounds. The bridging group may have the formula >ER¹R², wherein E maybe a carbon atom, a silicon atom, a germanium atom, or a tin atom, andwherein E is bonded to both η⁵-cyclopentadienyl-type ligands. In thisembodiment, R¹ and R² may be independently an alkyl group or an arylgroup, either of which having up to 12 carbon atoms, or hydrogen.

In embodiments of the present techniques, the ansa-metallocene of thepresent techniques may be expressed by the general formula:

(X¹)(X²)(X³)(X⁴)M¹.

In this formula, M¹ may be titanium, zirconium, or hafnium, X¹ may be asubstituted cyclopentadienyl, a substituted indenyl, or a substitutedfluorenyl. X may be a substituted cyclopentadienyl or a substitutedfluorenyl. One substituent on X¹ and X² is a bridging group having theformula ER¹R². E may be a carbon atom, a silicon atom, a germanium atom,or a tin atom, and is bonded to both X¹ and X². R¹ and R² may beindependently an alkyl group or an aryl group, either of which may haveup to 12 carbon atoms, or may be hydrogen. The bridging groups may beselected to influence the activity of the catalyst or the structure ofthe polymer produced. One substituent on X² may be a substituted or anunsubstituted alkyl or alkenyl group, which may have up to 12 carbonatoms. Substituents X³ and X⁴ may be independently: 1) F, Cl, Br, or I;2) a hydrocarbyl group having up to 20 carbon atoms, H, or BH₄; 3) ahydrocarbyloxide group, a hydrocarbylamino group, or atrihydrocarbylsilyl group, any of which may have up to 20 carbon atoms;4) OBR^(A) ₂ or SO₃R^(A), wherein R^(A) may be an alkyl group or an arylgroup, either of which may have up to 12 carbon atoms. Any additionalsubstituent on the substituted cyclopentadienyl, substituted indenyl,substituted fluorenyl, or substituted alkyl group may be independentlyan aliphatic group, an aromatic group, a cyclic group, a combination ofaliphatic and cyclic groups, an oxygen group, a sulfur group, a nitrogengroup, a phosphorus group, an arsenic group, a carbon group, a silicongroup, or a boron group, any of which may have from 1 to 20 carbonatoms. Alternatively, additional substituents may be present, includinghalides or hydrogen. The substituents on the η⁵-cyclopentadienyl-typeligands may be used to control the activity of the catalyst or thestereochemistry of the polymer produced.

An example of an ansa-metallocene that may be used in embodiments ispresented in EQN. 12, below.

In EQN. n, M¹ may be zirconium or hafnium and X′ and X″ may beindependently F, Cl, Br, or I. E may be C or Si and R¹ and R² may beindependently an alkyl group or an aryl group, either of which may haveup to 10 carbon atoms, or R¹ and R² may be hydrogen. R^(3A) and R^(3B)may be independently a hydrocarbyl group or a trihydrocarbylsilyl group,any of which may have up to 20 carbon atoms, or may be hydrogen. Thesubscript ‘n’ may be an integer that may range from 0 to 10, inclusive.R^(4A) and R^(4B) may be independently a hydrocarbyl group that may haveup to 12 carbon atoms, or may be hydrogen.

However, the catalyst systems of the present disclose are not limited tothe bridged metallocenes shown above. Indeed, any bridged or unbridgedmetallocene that forms high molecular weight copolymers with goodcomonomer incorporation may be used instead.

B. Solid Oxide Activator/Support

The present techniques encompass catalyst compositions that include anacidic activator-support, such as, for example, a chemically-treatedsolid oxide (CTSO). A CTSO may be used in combination with anorganoaluminum compound. The activator-support may include a solid oxidetreated with an electron-withdrawing anion. The solid oxide may includesuch compounds as silica, alumina, silica-alumina, aluminophosphate,aluminum phosphate, zinc aluminate, heteropolytungstates, titania,zirconia, magnesia, boria, zinc oxide, mixed oxides thereof, and thelike, or any mixture or combination thereof. The electron-withdrawinganion may include fluoride, chloride, bromide, iodide, phosphate,triflate, bisulfate, sulfate, sulfite, fluoroborate, fluorosulfate,trifluoroacetate, phosphate, fluorophosphate, fluorozirconate,fluorosilicate, fluorotitanate, permanganate, substituted orunsubstituted alkanesulfonate, substituted or unsubstitutedarenesulfonate, substituted or unsubstituted alkylsulfate, or anycombination thereof.

The activator-support may include the contact product of the solid oxidecompound and the electron-withdrawing anion source. Further, the solidoxide compound may include an inorganic oxide and may be optionallycalcined prior to contacting the electron-withdrawing anion source. Thecontact product may also be calcined either during or after the solidoxide compound is contacted with the electron-withdrawing anion source.In this embodiment, the solid oxide compound may be calcined oruncalcined. The activator-support may also include the contact productof a calcined solid oxide compound and an electron-withdrawing anionsource.

The solid oxide is not necessarily limited to the compounds discussedabove. Any number of other compounds, including oxides of zinc, nickel,vanadium, silver, copper, gallium, tin, tungsten, molybdenum, or anycombinations thereof, may be used. Examples of activator-supports thatfurther include an additional metal or metal ion include, for example,chlorided zinc-impregnated alumina, fluorided zinc-impregnated alumina,chlorided vanadium-impregnated alumina, fluorided zinc-impregnatedsilica-alumina, chlorided nickel-impregnated alumina, or anycombinations thereof. Further, other compounds may be used in additionto or in place of the solid oxide, such as borates, ionizing ioniccompounds, and the like.

C. Organoaluminum Compounds

The catalyst systems may include the unbridged metallocene catalysts ofthe present disclosure, a tightly-bridged ansa-metallocene compoundhaving an alkyl or alkenyl moiety bonded to a η⁵-cyclopentadienyl-typeligand, a solid oxide activator-support, and, an organoaluminumcompound. The organoaluminum compound may be omitted when it is notneeded to impart catalytic activity to the catalyst composition.

Organoaluminum compounds that may be used in the catalyst systemsinclude, for example, compounds with the formula:

Al(X⁵)_(n)(X⁶)_(3-n),

wherein X⁵ may be a hydrocarbyl having from 1 to about 20 carbon atoms;X⁶ may be alkoxide or aryloxide, any of which having from 1 to about 20carbon atoms, halide, or hydride; and n may be a number from 1 to 3,inclusive. In various embodiments, X⁵ may be an alkyl having from 1 toabout 10 carbon atoms. Moieties used for X⁵ may include, for example,methyl, ethyl, propyl, butyl, sec-butyl, isobutyl, 1-hexyl, 2-hexyl,3-hexyl, isohexyl, heptyl, or octyl, and the like. In other embodiments,X⁶ may be independently fluoride, chloride, bromide, methoxide,ethoxide, or hydride. In yet another embodiment, X⁶ may be chloride.

In the formula Al(X⁵)_(n)(X⁶)_(3-n), n may be a number from 1 to 3inclusive, and in an exemplary embodiment, n is 3. The value of n is notrestricted to an integer, therefore this formula may includesesquihalide compounds, other organoaluminum cluster compounds, and thelike.

Generally, organoaluminum compounds that may be used in the catalystsystems may include trialkylaluminum compounds, dialkylaluminium halidecompounds, dialkylaluminum alkoxide compounds, dialkylaluminum hydridecompounds, and combinations thereof. Examples of such organoaluminumcompounds include trimethylaluminum, triethylaluminum (TEA),tripropylaluminum, tributylaluminum, tri-n-butylaluminum (TNBA),triisobutylaluminum (TIBA), trihexylaluminum, triisohexylaluminum,trioctylaluminum, diethylaluminum ethoxide, diisobutylaluminum hydride,or diethylaluminum chloride, or any combination thereof. If theparticular alkyl isomer is not specified, the compound may encompass allisomers that can arise from a particular specified alkyl group.

D. The Olefin Monomer

In the present techniques, various unsaturated reactants may be usefulin the polymerization processes with catalyst compositions andprocesses. Such reactants include olefin compounds having from about 2to about 30 carbon atoms per molecule and having an olefinic doublebond. The present techniques encompass homopolymerization processesusing a single olefin such as ethylene or propylene, as well ascopolymerization reactions with two or more different olefiniccompounds. For example, in a copolymerization reaction with ethylene,copolymers may include a major amount of ethylene (>50 mole percent) anda minor amount of comonomer <50 mole percent. The comonomers that may becopolymerized with ethylene may have from three to about 20 carbon atomsin their molecular chain.

Olefins that may be used as monomer or comonomer include acyclic,cyclic, polycyclic, terminal (α), internal, linear, branched,substituted, unsubstituted, functionalized, and non-functionalizedolefins. For example, compounds that may be polymerized with thecatalysts of the present techniques include propylene, 1-butene,2-butene, 3-methyl-1-butene, isobutylene, 1-pentene, 2-pentene,3-methyl-1-pentene, 4-methyl-1-pentene, 1-hexene, 2-hexene, 3-hexene,3-ethyl-1-hexene, 1-heptene, 2-heptene, 3-heptene, the four normaloctenes, the four normal nonenes, the five normal decenes, or anycombination thereof. Further, cyclic and bicyclic olefins, including,for example, cyclopentene, cyclohexene, norbornylene, norbomadiene, andthe like, may also be polymerized as described above.

The amount of comonomer introduced into a reactor zone to produce acopolymer may be from about 0.001 to about 99 weight percent comonomerbased on the total weight of the monomer and comonomer, generally fromabout 0.01 to about 50 weight percent. In other embodiments, the amountof comonomer introduced into a reactor zone may be from about 0.01 toabout 10 weight percent comonomer or from about 0.1 to about 5 weightpercent comonomer. Alternatively, an amount sufficient to give the abovedescribed concentrations, by weight, of the copolymer produced, may beused.

While not intending to be bound by theory, it is believed that sterichindrance can impede or slow the polymerization process if branched,substituted, or functionalized olefins are used as reactants. However,if the branched and/or cyclic portion(s) of the olefin are somewhatremoved from the carbon-carbon double bond they would not be expected tohinder the reaction as much as more proximate substituents.

In exemplary embodiments, a reactant for the catalyst compositions ofthe present techniques is ethylene, so the polymerizations may be eitherhomopolymerizations or copolymerizations with a different acyclic,cyclic, terminal, internal, linear, branched, substituted, orunsubstituted olefin. In addition, the catalyst compositions of thepresent techniques may be used in polymerization of diolefin compounds,including for example, such compounds as 1,3-butadiene, isoprene,1,4-pentadiene, and 1,5-hexadiene.

Use of the Catalyst System in Polymerization Processes

The catalysts of the present techniques are intended for any olefinpolymerization method, using various types of polymerization reactors.As used herein, “polymerization reactor” includes any polymerizationreactor capable of polymerizing olefin monomers to produce homopolymersor copolymers. Such homopolymers and copolymers may be referred to asresins or polymers. The various types of reactors include those that maybe referred to as batch, slurry, gas-phase, solution, high pressure,tubular or autoclave reactors. Gas phase reactors may include fluidizedbed reactors or staged horizontal reactors. Slurry reactors may includevertical or horizontal loops. High pressure reactors may includeautoclave or tubular reactors. Reactor types may include batch orcontinuous processes. Continuous processes could use intermittent orcontinuous product discharge. Processes may also include partial or fulldirect recycle of un-reacted monomer, un-reacted comonomer, and/ordiluent.

Polymerization reactor systems of the present techniques may include onetype of reactor in a system or multiple reactors of the same ordifferent type. Production of polymers in multiple reactors may includeseveral stages in at least two separate polymerization reactorsinterconnected by a transfer device making it possible to transfer thepolymers resulting from the first polymerization reactor into the secondreactor. The desired polymerization conditions in one of the reactorsmay be different from the operating conditions of the other reactors.Alternatively, polymerization in multiple reactors may include themanual transfer of polymer from one reactor to subsequent reactors forcontinued polymerization. Multiple reactor systems may include anycombination including, but not limited to, multiple loop reactors,multiple gas reactors, a combination of loop and gas reactors, multiplehigh pressure reactors or a combination of high pressure with loopand/or gas reactors. The multiple reactors may be operated in series orin parallel.

A. Loop Slurry Polymerization Processes

In embodiments of the present techniques, the polymerization reactorsystem may include a loop slurry reactor. Such reactors may includevertical or horizontal loops. Monomer, diluent, catalyst and optionallyany comonomer may be continuously fed to the loop reactor wherepolymerization occurs. Generally, continuous processes may include thecontinuous introduction of a monomer, a catalyst, and a diluent into apolymerization reactor and the continuous removal from this reactor of asuspension including polymer particles and the diluent. Reactor effluentmay be flashed to remove the solid polymer from the liquids that includethe diluent, monomer and/or comonomer. Various technologies may beemployed for this separation step including but not limited to, flashingthat may include any combination of heat addition and pressurereduction; separation by cyclonic action in either a cyclone orhydrocyclone; or separation by centrifugation.

Loop slurry polymerization processes (also known as the particle formprocess) are are disclosed, for example, in U.S. Pat. Nos. 3,248,179,4,501,885, 5,565,175, 5,575,979, 6,239,235, 6,262,191 and 6,833,415,each of which is incorporated by reference in its entirety herein. Ifany definitions, terms, or descriptions used in any of these referencesconflicts with the usage herein, the usage herein takes precedence overthat of the reference.

Diluents that may be used in slurry polymerization include, for example,the monomer being polymerized and hydrocarbons that are liquids underreaction conditions. Examples of such diluents may include, for example,hydrocarbons such as propane, cyclohexane, isobutane, n-butane,n-pentane, isopentane, neopentane, and n-hexane. Some looppolymerization reactions can occur under bulk conditions where nodiluent may be used or where the monomer (e.g., propylene) acts as thediluent. An example is polymerization of propylene monomer as disclosedin U.S. Pat. No. 5,455,314, which is incorporated by reference in itsentirety herein.

B. Gas Phase Polymerization Processes

Further, the polymerization reactor may include a gas phase reactor.Such systems may employ a continuous recycle stream containing one ormore monomers continuously cycled through a fluidized bed in thepresence of the catalyst under polymerization conditions. A recyclestream may be withdrawn from the fluidized bed and recycled back intothe reactor. Simultaneously, polymer product may be withdrawn from thereactor and new or fresh monomer may be added to replace the polymerizedmonomer. Such gas phase reactors may include a process for multi-stepgas-phase polymerization of olefins, in which olefins are polymerized inthe gaseous phase in at least two independent gas-phase polymerizationzones while feeding a catalyst-containing polymer formed in a firstpolymerization zone to a second polymerization zone. One type of gasphase reactor is disclosed in U.S. Pat. Nos. 5,352,749, 4588,790 and5,436,304, each of which is incorporated by reference in its entiretyherein.

According to still another aspect of the techniques, a high pressurepolymerization reactor may include a tubular reactor or an autoclavereactor. Tubular reactors may have several zones where fresh monomer,initiators, or catalysts are added. Monomer may be entrained in an inertgaseous stream and introduced at one zone of the reactor. Initiators,catalysts, and/or catalyst components may be entrained in a gaseousstream and introduced at another zone of the reactor. The gas streamsmay be intermixed for polymerization. Heat and pressure may be employedappropriately to obtain optimal polymerization reaction conditions.

C. Solution Polymerization Processes

According to yet another aspect of the techniques, the polymerizationreactor may include a solution polymerization reactor wherein themonomer is contacted with the catalyst composition by suitable stirringor other means. A carrier including an inert organic diluent or excessmonomer may be employed. If desired, the monomer may be brought in thevapor phase into contact with the catalytic reaction product, in thepresence or absence of liquid material. The polymerization zone may bemaintained at temperatures and pressures that will result in theformation of a solution of the polymer in a reaction medium. Agitationmay be employed to obtain better temperature control and to maintainuniform polymerization mixtures throughout the polymerization zone.Adequate means may be utilized for dissipating the exothermic heat ofpolymerization.

D. Reactor Support Systems

Polymerization reactors suitable for the present techniques may furtherinclude any combination of a raw material feed system, a feed system forcatalyst or catalyst components, and/or a polymer recovery system. Suchsystems may include systems for feedstock purification, catalyst storageand preparation, extrusion, reactor cooling, polymer recovery,fractionation, recycle, storage, loadout, laboratory analysis, andprocess control, among others.

E. Polymerization Conditions

Conditions that may be controlled for polymerization efficiency and toprovide resin properties include temperature, pressure and theconcentrations of various reactants. Polymerization temperature canaffect catalyst productivity, polymer molecular weight and molecularweight distribution. Suitable polymerization temperature may be anytemperature below the de-polymerization temperature according to theGibbs Free energy equation. Typically this includes from about 60° C. toabout 280° C., for example, and from about 70° C. to about 110° C.,depending upon the type of polymerization reactor.

Suitable pressures will also vary according to the reactor andpolymerization type. The pressure for liquid phase polymerizations in aloop reactor is typically less than 1000 psig. Pressure for gas phasepolymerization is usually at about 200-500 psig. High pressurepolymerization in tubular or autoclave reactors is generally run atabout 20,000 to 75,000 psig. Polymerization reactors may also beoperated in a supercritical region occurring at generally highertemperatures and pressures. Operation above the critical point of apressure/temperature diagram (supercritical phase) may offer advantages.

The concentration of various reactants may be controlled to produceresins with certain physical and mechanical properties. The proposedend-use product that will be formed by the resin and the method offorming that product determines the desired resin properties. Mechanicalproperties include tensile, flexural, impact, creep, stress relaxationand hardness tests. Physical properties include density, molecularweight, molecular weight distribution, melting temperature, glasstransition temperature, temperature melt of crystallization, density,stereoregularity, crack growth, long chain branching and rheologicalmeasurements.

The concentrations of monomer, co-monomer, hydrogen, co-catalyst,modifiers, and electron donors may be important in producing these resinproperties. Comonomer may be used to control product density. Hydrogenmay be used to control product molecular weight. Co-catalysts may beused to alkylate, scavenge poisons and control molecular weight.Modifiers may be used to control product properties and electron donorsaffect stereoregularity. In addition, the concentration of poisons mustbe minimized since they impact the reactions and product properties.

Final Products made from Polymers

The polymer or resin fluff from the reactor system may have additivesand modifiers added to provide better processing during manufacturingand for desired properties in the end product. Additives include surfacemodifiers such as slip agents, antiblocks, tackifiers; antioxidants suchas primary and secondary antioxidants; pigments; processing aids such aswaxes/oils and fluoroelastomers; and special additives such as fireretardants, antistats, scavengers, absorbers, odor enhancers, anddegradation agents. After the addition of the additives, the polymer orresin fluff may be extruded and formed into pellets for distribution tocustomers and formation into final end-products.

To form end-products or components from the pellets, the pellets aregenerally subjected to further processing, such as blow molding,injection molding, rotational molding, blown film, cast film, extrusion(e.g., sheet extrusion, pipe and corrugated extrusion,coating/lamination extrusion, etc.), and so on. Blow molding is aprocess used for producing hollow plastic parts. The process typicallyemploys blow molding equipment, such as reciprocating screw machines,accumulator head machines, and so on. The blow molding process may betailored to meet the customer's needs, and to manufacture productsranging from the plastic milk bottles to the automotive fuel tanksmentioned above. Similarly, in injection molding, products andcomponents may be molded for a wide range of applications, includingcontainers, food and chemical packaging, toys, automotive, crates, capsand closures, to name a few.

Profile extrusion processes may also be used. Polyethylene pipe, forexample, may be extruded from polyethylene pellet resins and used in anassortment of applications due to its chemical resistance, relative easeof installation, durability and cost advantages, and the like. Indeed,plastic polyethylene piping has achieved significant use for watermains, gas distribution, storm and sanitary sewers, interior plumbing,electrical conduits, power and communications ducts, chilled waterpiping, and well casings, among others. In particular, high-densitypolyethylene (HDPE), which generally constitutes the largest volume ofthe polyolefin group of plastics used for pipe, is tough,abrasion-resistant and flexible (even at subfreezing temperatures).Furthermore, HDPE pipe may be used in small diameter tubing and in pipeup to more than 8 feet in diameter. In general, polyethylene pellets(resins) may be supplied for the pressure piping markets, such as innatural gas distribution, and for the non-pressure piping markets, suchas for conduit and corrugated piping.

Rotational molding is a high-temperature, low-pressure process used toform hollow parts through the application of heat to biaxially-rotatedmolds. Polyethylene pellet resins generally applicable in this processare those resins that flow together in the absence of pressure whenmelted to form a bubble-free part. Resins, such as those produced by thecatalyst compositions of the present techniques, may offer such flowcharacteristics, as well as a wide processing window. Furthermore, thesepolyethylene resins suitable for rotational molding may exhibitdesirable low-temperature impact strength, good load-bearing properties,and good ultraviolet (UV) stability. Accordingly, applications forrotationally-molded polyolefin resins include agricultural tanks,industrial chemical tanks, potable water storage tanks, industrial wastecontainers, recreational equipment, marine products, plus many more.

Sheet extrusion is a technique for making flat plastic sheets from avariety of resins. The relatively thin gauge sheets are generallythermoformed into packaging applications such as drink cups, delicontainers, produce trays, baby wipe containers and margarine tubs.Other markets for sheet extrusion of polyolefin include those thatutilize relatively thicker sheets for industrial and recreationalapplications, such as truck bed liners, pallets, automotive dunnage,playground equipment, and boats. A third use for extruded sheet, forexample, is in geomembranes, where flat-sheet polyethylene material maybe welded into large containment systems for mining applications andmunicipal waste disposal.

The blown film process is a relatively diverse conversion system usedfor polyethylene. The American Society for Testing and Materials (ASTM)defines films as less than 0.254 millimeter (10 mils) in thickness.However, the blown film process can produce materials as thick as 0.5millimeter (20 mils), and higher. Furthermore, blow molding inconjunction with monolayer and/or multilayer coextrusion technologieslays the groundwork for several applications. Advantageous properties ofthe blow molding products may include clarity, strength, tearability,optical properties, and toughness, to name a few. Applications mayinclude food and retail packaging, industrial packaging, andnon-packaging applications, such as agricultural films, hygiene film,and so forth.

The cast film process may differ from the blown film process through thefast quench and virtual unidirectional orientation capabilities. Thesecharacteristics allow a cast film line, for example, to operate athigher production rates while producing beneficial optics. Applicationsin food and retail packaging take advantage of these strengths. Finally,polyolefin pellets may also be supplied for the extrusion coating andlamination industry.

Ultimately, the products and components formed from polyolefin (e.g.,polyethylene) pellets may be further processed and assembled fordistribution and sale to the consumer. For example, a polyethylene milkbottle may be filled with milk for distribution to the consumer, or thefuel tank may be assembled into an automobile for distribution and saleto the consumer.

EXAMPLES Reagents

Unless otherwise noted, all operations were performed under purifiednitrogen or vacuum using standard Schlenk or glovebox techniques.Diethyl ether and THF were purchased anhydrous from Aldrich and used asreceived. Toluene and pentane were degassed and dried over activatedalumina. Heptane (Fisher Scientific) was degassed, and stored overactivated 13× molecular sieves under nitrogen.Tetrakis(dimethylamino)zirconium was purchased from Strem. Zirconiumtetrachloride, zirconium tetrakis(diethylamide), and hydrogen chloridesolution in diethyl ether (2.0 M) were purchased from Sigma-Aldrich andused as received. Celite (Celite 545, Sigma-Aldrich) was dried forseveral days at 90-100° C. prior to use. C₆D₆ (Cambridge IsotopeLaboratories) was stored over activated 13× molecular sieves undernitrogen. All other reagents not specified above were obtained fromAldrich Chemical Company and used without further purification.Li[C₅H₄—{(CH₂)₃CH₃}] was prepared by the reaction ofn-butylcyclopentadiene with an equimolar amount of n-butyl lithium(Sigma-Aldrich, 2.5 M in hexanes) in diethyl ether.Li[C₉H₆-1-(CH₂CH=CH₂)] was prepared by the reaction of1-(prop-1-en-3-yl)indene with an equimolar amount of n-butyl lithium(Sigma-Aldrich, 2.5 M in hexanes) in heptane. NMR spectra were recordedusing capped NMR tubes at ambient probe temperature. ¹H and ¹³C chemicalshifts are reported versus SiMe₄ and were determined by reference to theresidual ¹H and ¹³C solvent peaks. Coupling constants are reported inHz.

Example 1 Preparation of(1-allylindenyl)(n-butylcyclopentadienyl)zirconium dichloride

To Tetrakis(dimethylamino)zirconium (0.52 g, 1.94 mmol) dissolved intoluene (9 mL) was added allylindene (0.31 g, 1.99 mmol) at roomtemperature. The mixture was stirred at room temperature overnight.Removal of the solvent gave an oil. To the oil was added Me₃SiCl (7.5 mLof 1 M in methylene chloride, 7.5 mmol) at room temperature. The mixturewas stirred at room temperature overnight. Removal of the solvent gave ayellow solid (crude allylindenylzirconium trichloride). The yellow solid(crude allylindenylzirconium trichloride) was dissolved in THF (10 mL).N-BuCpLi (0.273 g, 2.13 mmol) dissolved in THF (5 mL) was added to aboveTHF solution (allylindenylzirconium trichloride/THF solution) at 0° C.The mixture was stirred at 0° C. for 30 minutes, then warned to roomtemperature and stirred for another 2.5 hours. The solvent was removed.The residue was extracted with toluene (30 mL). The supernatant wasseparated from the solid. Removal of the solvent gave a pale yellowsolid. The pale yellow solid was washed with pentane (30 mL) and thendried under vacuum. The desired compound was obtained as a pale yellowsolid (0.43 g, 51% overall yield). The product was identified by ¹H-NMR(FIG. 1). The product was not further purified and contained smallamount of impurity (bis(n-butylcyclopentadienyl)zirconium dichloride,about 6 mol % based on the integrals in ¹H-NMR of the product).

Example 2 Preparation of(1-allylindenyl)(n-butylcyclopentadienyl)zirconium dichloride

To Tetrakis(dimethylamino)zirconium (0.52 g, 1.94 mmol) dissolved intoluene (6 mL) was added allylindene (0.31 g, 1.99 mmol) at roomtemperature. The mixture was stirred at room temperature overnight. Tothe mixture was added Me₃SiCl (1 mL, 7.9 mmol) at room temperature. Themixture was stirred at room temperature overnight. Removal of thesolvent gave a yellow solid (crude allylindenylzirconium trichloride).The yellow solid (crude allylindenylzirconium trichloride) was dissolvedin THF (10 mL). N-BuCpLi (0.276 g, 2.15 mmol) dissolved in THF (6 mL)was added to above THF solution (allylindenylzirconium trichloride/THFsolution) at 0° C. The mixture was stirred at 0° C. for 30 minutes, thenwarned to room temperature and stirred for another 2.5 hours. Thesolvent was removed. The residue was extracted with toluene (30 mL). Thesupernatant was separated from the solid. Removal of the solvent gave ayellow solid. The yellow solid was washed with pentane (30 mL) and thendried under vacuum. The desired compound was obtained as a pale yellowsolid (0.54 g, 64% overall yield). The product was identified by ¹H-NMR(FIG. 2).

Example 3 Preparation of Zr{N(CH₂CH₃)₂}₂Cl₂(C₄H₈O)₂ from ZrCl₄ andZr{N(CH₂CH₃)₂}₄

A flask was charged with zirconium tetrachloride (6.842 g, 29.36 mmol)and diethyl ether (100 mL), and was cooled in an ice water bath. Asolution of zirconium tetrakis(diethylamide) (11.15 g, 29.36 mmol) indiethyl ether (30 mL) was prepared and added by cannula to the stirredsuspension of zirconium tetrachloride over 1 min. Neat tetrahydrofuran(20.0 mL, 247 mmol) was added by syringe to the stirred suspension. Thereaction mixture was stirred for 16 h and allowed to warm to 22 deg C.The resulting yellow suspension was concentrated to a volume of 50 mL byevaporation of solvent under vacuum. The mixture was cooled to −45 degC. for 24 h. The resulting clear supernatant solution was decanted coldfrom the precipitate by cannula. The precipitate was dried under vacuumfor 30 min to afford the desired product as a white solid (20.15 g,76%). A sample of this material (ca. 50 mg) was removed and dissolved inC₆D₆ (0.5 mL) to afford a clear pale-yellow solution. This solution wassubjected to NMR analysis, which showed that the material was pure. ¹HNMR (C₆D₆): δ 3.87 (m, 8H, OCH₂), 3.71 (q, J=7, 8H, NCH₂), 1.33 (m, 8H,OCH₂CH₂), 1.29 (t, J=7, 12H, NCH₂CH₃). ¹³C{¹H} NMR (C₆D₆): δ 72.2, 43.4,26.2, 13.8.

Example 4 Preparation of Zr(η⁵-C₅H₄—{(CH₂)₃CH₃}){N(CH₂CH₃)₂}₂Cl

A flask was charged with Zr{N(CH₂CH₃)₂}₂Cl₂(C₄H₈O)₂ (12.31 g, 27.33mmol) and toluene (50 mL). A solution of Li[C₅H₄—{(CH₂)₃CH₃}] (3.501 g,27.33 mmol) in tetrahydrofuran (40 mL) was prepared and added by cannulato the stirred solution of Zr{N(CH₂CH₃)₂}₂Cl₂(C₄H₈O)₂ over 1 min. Thereaction mixture was stirred solution of the solvent was evaporatedunder vacuum. The residue was suspended in heptane (10 mL) and filteredthrough a bed of Celite on a medium glass frit. The Celite was washedwith heptane (2×20 mL), and the filtrate and washes were combined. Theresulting solution was evaporated under vacuum to afford the desiredproduct as an orange oil (10.47 g, 98%). A sample of this material (ca.50 mg) was removed and dissolved in C₆D₆ (0.5 mL) to afford a clearyellow solution. This solution was subjected to NMR analysis, whichshowed that the material was pure. ¹H NMR (C₆D₆): δ 5.99 (t, J=3, 2H,Cp), 5.96 (t, J=3, 2H, Cp), 3.37 (m, 4H, NCH₂), 3.16 (m, 4H, NCH₂), 2.65(t, J=8, 2H, CpCH₂), 1.54 (p, J=8, 2H, CpCH₂CH₂), 1.30 (sextet, J=8, 2H,CpCH₂CH₂CH₂), 0.98 (t, J=7, 12H, NCH₂CH₃), 0.88 (t, J=8, 3H,CpCH₂CH₂CH₂CH₃). ¹³{¹H} NMR (C₆D₆): δ 131.5, 110.1, 44.2, 34.5, 30.6,23.8, 15.9, 15.2.

Example 5 Preparation of racemicZr(η⁵-C₅H₄—{(CH₂)₃CH₃}){η⁵-C₉H₆-1-(CH₂CH═CH₂)}{N(CH₂CH₃)₂}₂

A flask was charged with Zr(η⁵-C₅H₄—{(CH₂)₃CH₃}){N(CH₂CH₃)₂}₂Cl (3.922g, 10.00 mmol) and diethyl ether (15 mL). A solution ofLi[C₉H₆-1-(CH₂CH═CH₂)] (1.622 g, 10.00 mmol) in diethyl ether (15 mL)was prepared and added by cannula to the stirred solution ofZr(η⁵-C₅H₄—{(CH₂)₃CH₃}){N(CH₂CH₃)₂}₂Cl over 1 min. The reaction mixturewas stirred for 30 min and the solvent was evaporated under vacuum. Theresidue was suspended in heptane (30 mL) and filtered through a bed ofCelite on a medium glass frit. The Celite was washed with heptane (2×30mL), and the filtrate and washes were combined. The resulting solutionwas evaporated under vacuum to afford the desired product as a red oil(5.050 g, 99%). A sample of this material (ca. 50 mg) was removed anddissolved in C₆D₆ (0.5 mL) to afford a clear orange-red solution. Thissolution was subjected to NMR analysis, which showed that the materialwas pure. ¹H NMR (C₆D₆): δ 7.52 (m, 2H, Ind-C₆), 7.05 (m, 2H, Ind-C₆),6.57 (d, J=3, 1H, Ind-C₅), 6.03 (m, 1H, CH═CH₂), 5.80 (q, J=2, 1H, Cp),5.72 (d, J=3, 1H, Ind-C₅), 5.71 (q, J=2, 1H, Cp), 5.36 (q, J=2, 1H, Cp),5.31 (q, J=2, 1H, Cp), 5.13 (dq, J=16, 1; 1H, CH═CH₂), 5.03 (dq, J=16,1; 1H, CH═CH₂), 3.65 (m, 2H, CH₂CH═CH₂), 3.25 (m, 8H, NCH₂), 2.29 (m,2H, CpCH₂), 1.46 (p, J=7, 2H, CpCH₂CH₂), 1.26 (sextet, J=7, 2H,CpCH₂CH₂CH₂), 1.06 (t, J=7, 6H, NCH₂CH₃), 0.99 (t, J=7, 6H, NCH₂CH₃),0.94 (t, J=7, 3H, Me). ¹³C{¹H} NMR (C₆D₆): δ 138.0, 131.9, 131.1, 123.1,122.1, 121.8, 121.7, 121.1, 115.1, 115.0, 112.5, 112.3, 110.1, 109.8,89.4, 66.4, 47.0, 46.7, 35.1, 34.1, 30.1, 23.7, 16.5, 16.0, 15.8, 15.1.

Example 6 Preparation of racemicZr(η⁵-C₅H₄—{(CH₂)₃CH₃}){η⁵-C₉H₆-1-(CH₂CH═CH₂)}Cl₂

A flask was charged with racemicZr(η⁵-C₅H₄-{(CH₂)₃CH₃}){η⁵-C₉H₆-1-(CH₂CH═CH₂)}{N(CH₂CH₃)₂}₂ (5.000 g,9.768 mmol) and diethyl ether (50 m was cooled in an ice water bath. Asolution of HCl in diethyl ether (10 mL, 2.0 M, 20 mmol) was added bysyringe to the stirred solution of racemicZr(η⁵-C₅H₄-{(CH₂)₃CH₃}){η⁵-C₉H₆-1-(CH₂CH═CH₂)}{N(CH₂CH₃)₂}₂ over 1 min.The mixture was stirred for 15 min, and the bath was removed. Themixture was stirred for 30 min and diethyl ether (50 mL) was added bycannula. The resulting yellow slurry was filtered on a medium glassfrit. The filtered precipitate was dried under vacuum to afford thedesired product as pale-yellow solid (1.549 g, 35%). A sample of thismaterial (ca. 50 mg) was removed and dissolved in CDCl₃ (0.5 mL) toafford a clear yellow solution. This solution was subjected to NMRanalysis, which showed that the material was pure desired compound basedon comparison with previously reported data (FIG. 5).

While the techniques disclosed above may be susceptible to variousmodifications and alternative forms, specific embodiments have beenshown by way of example in the drawings. However, it should beunderstood that the techniques are not intended to be limited to theparticular forms disclosed. Rather, the techniques encompass allmodifications, equivalents and alternatives falling within the spiritand scope of the techniques as defined by the following appended claims.

1. A catalyst precursor, comprising a general structure of:

wherein M is Zr or Hf; each x is independently a hydrogen, alkyl,branched alkyl, cycloalkyl, alkylene, aryl, arylene, alkenyl, oralkenylene group having from 2 to 20 carbons; at least one x is aterminal, branched, or internal alkenyl group having from 2 to 20carbons; each Y is independently a halide or NR₂, wherein each R isindependently a hydrocarbyl group having from 1 to 5 carbons; and each cis independently a hydrogen, alkyl, branched alkyl, cycloalkyl, aryl, oralkenyl group having from 2 to 20 carbons.
 2. The catalyst precursor ofclaim 1, wherein M is Zr.
 3. The catalyst precursor of claim 1,comprising a general structure of:


4. The catalyst precursor of claim 1, comprising a general structure of:

wherein n is 1, 2, 3, 4, 5, 6, 7, or
 8. 5. (canceled)
 6. The catalystprecursor of claim 1, comprising a general structure of:

wherein n is 1, 2, 3, 4, 5, 6, 7, or
 8. 7. The catalyst precursor ofclaim 1, wherein at least one c is conjoined with another c to form aring.
 8. A method for making a catalyst precursor, comprising: reactinga compound with M(NR₂)₄ to form a product, wherein: the compound has ageneral structure of:

wherein: each x is independently selected from a hydrogen, alkyl,branched alkyl, cycloalkyl, aryl, or alkenyl group having from 2 to 20carbons; and at least one x is a terminal, branched, or internal alkenylgroup having from 2 to 20 carbons; each c is independently selected froma hydrogen, alkyl, branched alkyl, cycloalkyl, aryl, or alkenyl grouphaving from 2 to 20 carbons; M is Ti, Zr, or Hf; each R is independentlya hydrocarbyl group having from 1 to 5 carbons; and the product has ageneral structure of:


9. The method of claim 8, comprising: reacting the product with achlorinating agent to form a second product having a general structureof:


10. The method of claim 9, wherein the chlorinating agent comprisesMe₃SiCl, HCl, Me₂NH/HCl, or any combinations thereof.
 11. A method formaking a catalyst precursor, comprising: reacting a compound with agroup I or group II metallating agent to form a first product, wherein:the compound has a general structure of:

wherein: each x is independently selected from a hydrogen, alkyl,branched alkyl, cycloalkyl, aryl, or alkenyl group having from 2 to 20carbons; and at least one x is a terminal, branched, or internal alkenylgroup having from 2 to 20 carbons; each c is independently selected froma hydrogen, alkyl, branched alkyl, cycloalkyl, aryl, or alkenyl grouphaving from 2 to 20 carbons; and the metallating agent is a group I orgroup II metal, or is a group I or group II metal alkyl, hydrocarbyl,amide, alkoxide, aryloxide, hydride, borohydride, sulfide, selenide,phosphide or substituted variant thereof; and the first product has ageneral structure of:

wherein A comprises the group I or group II metal; and reacting thefirst product with MY₄L_(n) to form a catalyst precursor, wherein: M isTi, Zr, or Hf; each Y is independently a halide or NR₂, wherein each Ris a hydrocarbyl group having from 1 to 5 carbons; and each L is amonodentate or multidentate neutral or zwitterionic donor including butnot limited to ethers, cyclic ethers, amines, phosphines, nitriles,pyridines, thioethers and substituted variants thereof; n is 0 or 2; andthe catalyst precursor has a general structure of:


12. A method for making a catalyst precursor, comprising: reacting acompound with HaSiR₃ in the presence of a metal alkyl compound to form afirst product, wherein: the compound has a general structure of:

wherein: each x is independently selected from a hydrogen, alkyl,branched alkyl, cycloalkyl, aryl, or alkenyl group having from 2 to 20carbons; at least one x is a terminal, branched, or internal alkenylgroup having from 2 to 20 carbons; and at least one x is a hydrogen;each c is independently selected from a hydrogen, alkyl, branched alkyl,cycloalkyl, aryl, or alkenyl group having from 2 to 20 carbons; Ha is F,Cl, Br, or I; each R is independently a hydrocarbyl group having from 1to 5 carbons; and the first product has a general structure of:

wherein one z is R₃Si—; each remaining z is independently a hydrogen,alkyl, branched alkyl, cycloalkyl, aryl, or alkenyl group having from 2to 20 carbons; at least one z is a terminal, branched, or internalalkenyl group having from 2 to 20 carbons; and reacting the firstproduct with MY₄L_(n) to form a catalyst precursor, wherein: M is Zr orHf; each Y is independently a halide or NR₂, wherein each R is ahydrocarbyl group having from 1 to 5 carbons; and each L is amonodentate or multidentate neutral or zwitterionic donor including butnot limited to ethers, cyclic ethers, amines, phosphines, nitriles,pyridines, thioethers and substituted variants thereof; n is 0 or 2; andthe catalyst precursor has a general structure of:

wherein: each w is independently a hydrogen, alkyl, branched alkyl,cycloalkyl, aryl, or alkenyl group having from 2 to 20 carbons; one w isa hydrogen; and at least one w is a terminal, branched, or internalalkenyl group having from 2 to 20 carbons. 13-21. (canceled)
 22. Acatalyst precursor, comprising a general structure of:

wherein M is Ti, Zr, or Hf; each x is independently a hydrogen, alkyl,branched alkyl, cycloalkyl, aryl, or alkenyl group having from 2 to 20carbons; at least one x is a terminal, branched, or internal alkenylgroup having from 2 to 20 carbons; each Y is independently a halide orNR₂, wherein each R is independently a hydrocarbyl group having from 1to 5 carbons; at least one Y is NR₂; and each c is independently ahydrogen, alkyl, branched alkyl, cycloalkyl, aryl, or alkenyl grouphaving from 2 to 20 carbons.
 23. A method for making a catalystprecursor, comprising: reacting a compound with HaSiR₃ in the presenceof a metal alkyl compound to form a first product, wherein: the compoundhas a general structure of:

wherein: each x is independently selected from a hydrogen, alkyl,branched alkyl, cycloalkyl, aryl, or alkenyl group having from 2 to 20carbons; at least one x is a terminal, branched, or internal alkenylgroup having from 2 to 20 carbons; at least one x is a hydrogen; each cis independently selected from a hydrogen, alkyl, branched alkyl,cycloalkyl, aryl, or alkenyl group having from 2 to 20 carbons; Ha is F,Cl, Br, or I; each R is independently a hydrocarbyl group having from 1to 5 carbons; and the first product has a general structure of:

wherein one z is R₃Si—; each remaining z is independently a hydrogen,alkyl, branched alkyl, cycloalkyl, aryl, or alkenyl group having from 2to 20 carbons; and at least one z is a terminal, branched, or internalalkenyl group having from 2 to 20 carbons; and reacting the firstproduct with MY₄L_(n) to form a catalyst precursor, wherein: M is Ti,Zr, or Hf; each Y is independently a halide or NR₂, wherein each R is ahydrocarbyl group having from 1 to 5 carbons; each L is a monodentate ormultidentate neutral or zwitterionic donor including but not limited toethers, cyclic ethers, amines, phosphines, nitriles, pyridines,thioethers and substituted variants thereof; and n is 0 or 2; and thecatalyst precursor has a general structure of:

wherein: each w is independently a hydrogen, alkyl, branched alkyl,cycloalkyl, aryl, or alkenyl group having from 2 to 20 carbons; one w isa hydrogen; at least one w is a terminal, branched, or internal alkenylgroup having from 2 to 20 carbons; and at least one Y is NR₂.
 24. Acatalyst precursor, comprising a general structure of:

wherein n is 1, 2, 3, 4, 5, 6, 7, or
 8. 25. A catalyst precursor,comprising a general structure of:

wherein each x is independently a hydrogen, alkyl, branched alkyl,cycloalkyl, aryl, or alkenyl group having from 2 to 20 carbons; at leastone x is a terminal, branched, or internal alkenyl group having from 2to 20 carbons; each R is independently a hydrocarbyl group having from 1to 5 carbons; and each c is independently a hydrogen, alkyl, branchedalkyl, cycloalkyl, aryl, or alkenyl group having from 2 to 20 carbons.26. A method for making a catalyst precursor, comprising: reacting acompound with HaSiR₃ in the presence of a metal alkyl compound to form afirst product, wherein: the compound has a general structure of:

wherein: each x is independently selected from a hydrogen, alkyl,branched alkyl, cycloalkyl, aryl, or alkenyl group having from 2 to 20carbons; at least one x is a terminal, branched, or internal alkenylgroup having from 2 to 20 carbons; at least one x is a hydrogen; each cis independently selected from a hydrogen, alkyl, branched alkyl,cycloalkyl, aryl, or alkenyl group having from 2 to 20 carbons; Ha is F,Cl, Br, or I; each R is independently a hydrocarbyl group having from 1to 5 carbons; and the first product has a general structure of:

wherein one z is R₃Si—; each remaining z is independently a hydrogen,alkyl, branched alkyl, cycloalkyl, aryl, or alkenyl group having from 2to 20 carbons; and at least one z is a terminal, branched, or internalalkenyl group having from 2 to 20 carbons; and reacting the firstproduct with Ti(NR₂)₄L_(n) to form a catalyst precursor, wherein: each Ris a hydrocarbyl group having from 1 to 5 carbons; each L is amonodentate or multidentate neutral or zwitterionic donor including butnot limited to ethers, cyclic ethers, amines, phosphines, nitriles,pyridines, thioethers and substituted variants thereof; and n is 0 or 2;and the catalyst precursor has a general structure of:

wherein: each w is independently a hydrogen, alkyl, branched alkyl,cycloalkyl, aryl, or alkenyl group having from 2 to 20 carbons; one w isa hydrogen; at least one w is a terminal, branched, or internal alkenylgroup having from 2 to 20 carbons.